The present invention relates to an end terminating arrangement for plastic and rubber conduit and more particularly to the securement of connectable male or female connector fittings onto the terminal ends o flexible resilient conduit.
As connector fittings become more and more popular in industry, the applications for connector fittings become ever increasing. Connector fittings play an important role in connecting conduits together in compressed air and low pressure hydraulic piping systems and in fluid apparatus. Further, connector fittings may be adapted for other tasks such as where a removable and insertable connection is needed between conduits or the like.
Generally, connectable male and female connector fittings are assembled on flexible conduits by the manufacturer. However, a standard size conduit having factory fittings will not always work in the field. Thus, there is a need in the art to position male or female connector fittings onto flexible conduit out in the field. Prior devices for positioning connectable connector fittings onto the terminal end of flexible conduit out in the field required the use of clamps. Although clamps are adequate for positioning male and female fittings on the terminal ends of conduits, the clamps are easily stripped when tightened by a screwdriver or the like. Heating is used to position male and female fittings onto the terminal ends of conduit. The heating, if not executed properly, has a tendency to melt or deform the plastic and/or rubber conduit, ruining the conduit. Also, self securing connector fittings which cut into the surface of the conduit are used to secure the connector fitting onto the terminal ends of the conduit. However, the self-securing fitting has a tendency to penetrate the conduit surface causing a weak spot in the conduit. Further, adhesives are used to secure connector fittings onto the terminal ends of conduits. However, adhesives are sloppy, require several solvents, and need time to set-up before use. Other disadvantages of the prior connector fitting securements will be apparent to those skilled in the art.
Accordingly, it is an objective of the present invention to overcome the disadvantages of securing prior connector fittings to the terminal ends of flexible conduits out in the field. The present invention provides the user with a connectable fitting which is easily secured with a minimum amount of skill. The present invention provides the art with a new and improved apparatus for positioning a connectable male or female connector fitting onto terminal ends of flexible resilient conduits. The connector apparatus in accordance with the present invention can easily be secured onto the terminal end of a flexible conduit by a pressure fit eliminating the uncertainties involved with clamping, heating, adhesives, and penetration fittings.
The present invention includes a first member positioned about the exterior surface of the terminal end of the flexible conduit. A second member is positioned about the interior surface of the terminal end of the conduit. A mechanism acting as a male or female connector fitting is coupled with either the first o second member. The two members are securely affixed, by a pressure fit, to the terminal end of the conduit forming a connectable connector fitting o the terminal end of the conduit.
The first member may have a projecting member for providing the fitting with a surface for securing the connector fitting into a female connector fitting. Also, a female connector fitting may be continuous with either the first member or second member for providing the terminal end of the conduit with a female fitting. The first and second members may be continuous with one another forming a connector fitting on the terminal end of a conduit. The first and second members may be separate and distinct members forming a two piece connector fitting.
Generally, the first member includes a cylindrical body portion positioned about the exterior surface of the conduit. The body portion has at least one discontinuity in its surface for improving the affixing of the conduit between the first and second member.
Generally, the second member includes a cylindrical body portion positioned on the interior surface of the terminal end of the conduit. The cylindrical body portion has a peripheral bead on its exterior surface for improving the affixment of the conduit between the first and second members.
The method disclosed herein permits the use of the deep drawing progressive stamping manufacturing process which allows generally cylindrical parts to be formed from thin metal strip stock. The exceedingly close and repeatable tolerances and smooth surface finishes that are common to this process allow the manufacturer of conduit attachment components to precisely control dimensions whereby the user can obtain an attachment in the field that is as accurate as the best factory made attachment.
Although attachments to conduit having a thin wall and formed of plastic are known, material imperfections can undesirably lead to failures such that only relatively noncritical applications have been considered for terminating conduit that is larger than about 8 mm. in inside diameter. The cost of the plastic material generally results in the conduit wall thickness being held to a minimum which has the effect of severely limiting the performance of larger diameter conduit attachments, even though the conduit itself is capable of better performance. Nylon and other harder plastics permit the use of non-reinforced tubing but have not reduced user costs because of the reliability of the termination arrangement. The best currently available terminations usually involve wrenching and torquing arrangements which are operator sensitive. Where these attachment arrangements are also combined with a fitting that must be pre-installed on a device being connected by the conduit, space limitations prevent reliable wrenching to secure to the conduit. These prior art attachment arrangements are relatively expensive when compared to the attachment arrangements disclosed herein. The attachment arrangement, in accordance with this invention, makes possible the reliable use of lower cost high-performance conduit and use of quick connectors of the nature of those described in U.S. Pat, Nos. 4,423,892 and 4,541,658, assigned to the same assignee as the present invention, the disclosures of which are herein incorporated by reference.
From the subsequent description and the appended claims taken in conjunction with the accompanying drawings, other objects and advantages of the present invention will become apparent to one skilled in the art.